Manufacture of cupric chloride



`lan. 9, 1945.

QF.` swlNEHART ET AL.

` MANUFACTURE oF CUPRIG CHLORIDE Filed NOV. 15. 1941 Fig.

I. o. Hag

HSrVENrORs.V

` ATTORNEY.

vthe heat 0f reaction in Peienied Jen. 9, 1945 iuANuIfsc'rUnE-OF cPnIcCHLoRmE carl F. swinehe'rt, University Heights, and Jenn A.10. Hay, Y

`Theilflarshaw Cleveland Heights, `0hio, Chemical Company, Elyria, Ohio, 4

. corporaton'of Ohio assignors to ApplieatienNcvember 15, 1941, seriaiiv0.4`19',s12 f feelings. .floll.zssdl' This l invention-relates to @the fproductionf of cupric chloride and has for its principal object to provldea continuous process for rapid production of -such' materialinvolving the Vuse'of metallic or'massive copperand chlorine asfstartingmatel rials.,. Al further objectris to providegacontinuous process, by V:means of which botlrcupnic and cuprous chloridefmay.bcffprcduced making use of the .same apparatusfand producingggoption, fly cupric chloride or cuprous chloride. Y

ride .and copper to iorm cuprous chloride is the principal reaction which takes place in the region i of Sthetower containing the coppen, The solution y enriched ,with cuprous chloride is free to circulate Other and more limited objects will :be in lpart obvious from the follow.ing description,-v4 andY in part pointedfout in connection with the accompanying drawing, wherein Fig. l isfa schematic, l

vertical, sectional yiewgofapparatus employed in connection with my novel process; Fig.`2 is a section corresponding substantially'to `the line '2--2 oit-Eig. 1; andFigl 3 isla flowdiagram. illustrating the present preierred embodiment of the, process. -Reier1ingnow-to theaccompanying drawing,

the process willbe" described :inv connection 'with V the apparatus whichl we preferto em ploy1 YAV` ,TheV` reference characterl A indicates generally a tower .whichm'ay be,com po,sed lof .chemical stoneware,- glass, or the like.. The tower A is provided with a seriesof dividing perforated plates or partitions; I to. 5, inclusive. Above the perforated plates I to ,inclusivenwe.provide 'suit'- able packing, such as .Raschigrin'ga glassbeads, orthe like.A Above the'uppermo/st'plate 5, we

,provide al Y suitable quantity of Lmassive copper which may bein the. form'of, wire, clippings,^ shot,

or the. like. l.More copper .metal is" added as the reacticnproceeds.. Y i e Chlorine is ntroducedtouthe bottom ofthe tower `throughthe conduit 6, itbeingl understood that this conduitmaybe connected to agsuitable supply Aof gaseou'schlorine, {suchfas a cylinder, tank car, or thelikef AStea'rvn maybe introduced through the conduit 1 in order tu'V produce in the tower a suitable solution temperature to start'the reaction Kandsupplement to the extent necessary Y Y H maintaining the Solution at suitable Aworking temperature v' j f However, in the preferred method of operation, heat beyond the-heater 'reaction' is vnot required to any great extent,u if at all,`except in. starting the reactior'i.`v` l e the' reaction betweencuprflcchloridefand massive copper becomes sufllciently rapid to'become selfsup'pox'ting, and of Aindustrial significance is about 70 C., a'lthoughthis is` somewhat'dependent on ofthe solution. The'optimum temperature Afor the region of-the tower nwhichtheA above reaction occurs is, however,of the orderv of 100 C. 'to 110 C. This gives a high reaction rate, and

at the-same time permits a relatively high concentration of copper in solution;

The reaction occurring between cupric chlo- The` minimum i temperature at whichV around and through the copper in this (upper) sectionof the tower containing the copper metal and to a somewhat -less extent yinto the zone di- .rectly beneath it. In this zone and under some conditions in the'fbottom'part of the section containing copper wire, there is a considerable amountof-reaction between the cuprous chloride andchlorine to form cupric chloride. A substantial portion of this solutionv richer in cupric chlo- :ride ris circulated upward through .the copper wire',

beingaided in this-recirculation by boiling of the solution `if the optimum operating temperature is beingmaintained.

jThe net, result isthe rformation in the-upper part of the tower of a concentratedv solution of cuprous. and. cupric chloride by two reactionsv whichv proceed almost;A as if at the'saine location. Nevertheless, they do occur mainly in separate regionsof the-tower, although the result is such Y rapid-action'.as almost to suggest directvreaction of chlorine with copper. A,

f A portion ofthe cuprous Vand cupric chloride solution passes continuously Vdownward and out of the zone of `active recirculation and then progresislvelyv4 through the lower sections of the tower. In the lower part of the tower convection recirculation iselectivelyreduced by means of per- Aforatedbaiilelplates.Y In this lower part of the tower, lthe reactionV between cuprous chloride and chlorine is` promoted by the countercurren.,

lflow of the :upward passing chlorine, so that the solutiondrawn vfromthe bottom of the tower is essentiallyiiree of all the cuprous chloride and may be practically saturated Vwith cupric chloride-.and ready to crystallize on cooling.

While a single packed column of suitable length vwill accomplish vthe necessary suppression of con- Ythe size ofthe apparatus` andthe concentration vecton currents and limitation of recirculation, towerswith-'a diameter greater than 6'. or 8" require a height thatis apt to be prohibitively' great. In Vthe preferred method, asr illustrated (and describedV above), thelower parti-of the tower is considerably decreased Vin. height by being di- Avided'into` Ysections orindividual cells by means through the branch 8b. The branch 8c may contain a suitable valve or equivalent structure and maybe used for draining and removal of sludge. The mother liquor from the crystallizing tank may be returned through the opening 9 at the top of the tower, or may be simply introduced through the open ktop of theytower.

In Fig. 3, we have shown a iiow diagram wherein the tower is indicated by the reference character A, the crystallizing tank is indicated by the reference character B, and a neutralizing tank is indicated by the reference character C. As indicated in Fig. 3, the cupric chloride passes from the tower A to the crystallizing tank B where it is allowed to cool and thereby crystallizes out a portion of the cupric chloride.y A small proportion, suitably 10% or less based on CuClz content, of 'hydrochloric acid (calculated as HCl) is preferably added to promote crystallization. From the crystallizing tank, the mother liquor passes to the neutralizing tank C where a suiiicient amount of copper oxide is added to nearly neutralize the hydrochloric acid content. Thereafter, the `mother liquor or such portion thereof as may be found desirable together with a suitable quantity of water is returned to the tower A, being admitted through the opening 9.

'I'he addition of the hydrochloric acid to the crystallizing tank and subsequent neutralization of most of it is optional,d but it is preferred. The hydrochloric acid increases the yield of crystals as well as the rapidity with which they form and thus eliminates evaporation and/or klong cooling periods. The neutralization of the excess acid with CuO is economic because at the optimum operating concentrations and temperatures, the greater part of the HCl in such unneutralized mother liquors will be driven of! as gas from the tower and will, therefore, constitute a loss. However, a small amount of HCl is permissible and even desirable in order to dissolve any oxide or carbonate of copper which may be introduced as common impurities (oxidized surface coatings, etc.) in commercial metallic copper.

The return of mother liquor to the tower isv not essentialbut is highly desirable, since otherwise it would be necessary to evaporate water therefrom to recover the remaining CuClz-2H2O therefrom, at the same timeV adding water to the tower to maintain the solution of CuClz formed.

It is to be recommended that the rate of introduction of chlorine into the tower be such that very little gaseous chlorine, if any, is permitted to escape at the top of the tower. Also, the concentration of cuprlc chloride should be. adjusted, as far as possible, to avoid the recirculation of large quantities of mother liquor. It is possible, however, to operate within rather wide ranges in respect to solution concentration and rate of introduction of chloride, the particular conditions being dictated by considerations In the event it is desired to produce cuprous make either all CuClz or some of both. If CuCl is the entire product, some concentration by evaporation may be necessary.

While we have shown and described the present preferred embodiment uf our invention and have diagrammatioally indicated apparatus which may be employed in carrying it out, we do not wish to be limited to the details of the disclosure but only in accordance with the ap pended claims and the prior art.

What we claim is:

1. Process for producing a copper chloride from metallic copper and chlorine comprising chloride, liquid may be Withdrawn from the top of the tower. On cooling, a portion of the cuprous chloride will crystallize out. The mother liquor then maybe returned to the top of the tower there to build up again in cuprous chloride concentration. More Acupnous chloride crystals can be obtained if the hot solution from the top of the tower is passed over metallic copper before cooling. Again crystallization is promoted if the solution is diluted with water.

While it is thus obviously possible to make either all CuClz or all CuCl, it is preferable to continuously passing chlorine into the bottom section of a tower in the upper section of which metallic copper in such form as to'present a large area per unit weight is supported away from said bottom section, maintaining an aqueous solution of chlorides of copper extending-to a height in said tower covering at least a portion of said metallic copper, distributing the chlorine gas in tortuousV ow in said solution below and into said upper portion, continuously withdrawing solution from said tower and removing` a copper chloride from the solution so withdrawn.

2. Process for producing cupric chloride irom metallic copper and chlorine comprising continuously passing chlorine into the bottom section of a tower in the upper section of which metallic copper in such form as to present. a large area per unit weight is supported away from said bottom section, maintaining an aqueous solution of chlorides of copper extending to a height in said tower covering at least a portion of said metallic copper, distributing the chlorine gas in tortuous now in said solution below and into said upper portion, continuously withdrawing solution from the bottom of said tower and removing cupric chloride from the solution so withdrawn.

3. Process for producing cuprous chloride from metallic copper and chlorine comprising continuously passing chlorine into the bottom section of atower in the upper section of which metallic copper in such form as to present a large areajper unit weight is supported away from said bottom section, maintaining an aqueous solution of chlcrides of copper extending to a height in said tower covering at least a portion of said metallic copper,`distributing the chlorine sas in toruous flow in said solution below and into said upper portion, continuously withdrawing solution from the tcp of said tower and removing cuprous chloride from the solution so withdrawn.

4. Process for producing cupric chloride from metallic copper and chlorine comprising passing chlorine into the bottom section of a tower in the upper section of which metallic copper in such form as to present a large area per unit weight is supported away Ltrom said bottom section, maintaining an aqueous solution of chlorides of copper extending to a height in said tower covering at least a portion of said metallic copper, distributing the chlorine gas in tortuous now in said solution below and into said upper portion, withdrawing cupric chloride solution from the bottom section of said tower, crystallizing cupric chloride from said solution, and returning mother liquor to the upper section of said tower.

' CARL F. SWINEHART.

JOHN O. HAY. 

